1. Field of the Invention
Generally, the field of the present invention is high power optical amplification systems. More particularly, the present invention relates to high power optical amplification systems and methods utilizing chirally coupled core optical fibers.
2. Background
Laser systems have enjoyed successful penetration into a wide array of applications in the last several decades, both increasing efficiencies and enabling new technologies in material processing, drilling, electronic device manufacturing, and in other industrial and defense-related spaces. In particular, the advent of the fiber laser and fiber amplifier have allowed for even more applications, and enhancement of existing ones, as superior beam quality can be obtained in a fiber laser or fiber amplifier output beam due to the intrinsic nature of a fiber optic waveguide.
In particular, chirally coupled core fibers present a significant breakthrough in the performance of fiber lasers and amplifiers as they enable very large fundamental mode field diameters while maintaining diffraction limited beam quality, among other unique features. However, because chirally coupled core fibers are typically rotated during fabrication to form a helical geometry within the fiber, importing a conventional polarization maintaining design, such as panda or bow-tie, is not practical. This is because the polarization maintaining elements become rotated as well, causing the intrinsic birefringence they impart to rotate, thereby removing the ability to maintain a stable linear polarization. Moreover, as peak powers increase, effective limits on maximum achievable power surface due to the onset of parasitic nonlinear effects. Accordingly, there remains a need for systems employing chirally coupled core fibers without the attendant drawbacks.